zotero-updateifsE: Green Frog pulls journal metrics into Zotero

Journal metrics, fetched on demand from easyScholar

Green Frog is a Zotero plugin built around a data source rather than around Zotero itself. The README credits easyScholar for providing the data interface and describes easyScholar as a browser extension with useful journal data. The plugin's main action is available from the right-click menu on a collection or an item, or through a keyboard shortcut that defaults to Ctrl+J and can be changed or disabled in the settings. When triggered, the plugin decides what to ask for based on the item's language and then writes the results back into the item. For an English journal or a conference paper, where the conference name has to be put into the Conference Name field, it fetches the JCR quartile, the CAS quartile in both the basic and upgraded forms, the impact factor, the five year impact factor, EI status, the CAS upgraded Top quartile, the CAS upgraded sub-category quartile, and the CAS warning flag. For Chinese journals it fetches a longer list, including CSCD, PKU Core, NJU Core, Sci and Tech Core, SSCI, AJG, UTD24, FT50, CCF, FMS, JCI, AHCI, ESI, the compound and comprehensive impact factors, and the classification lists used by individual universities.

Results are stored in the Extra field, which has to be kept clean

The storage decision explains a lot of how the plugin behaves. The README states that the journal information is saved in the Extra field, which in the Zotero item pane is the field labelled "Extra". Because Zotero's Extra field is also where users keep their own notes, tags turned into lines, and sometimes citation data, a plugin writing structured metadata into it will collide with existing content. The README anticipates exactly this: if the display is not right, you clear the field first with Tools, Empty Extra Field, which is one of the plugin's own menu entries. The visible result is a column set in the library table, and the plugin lets you decide which fields appear. In Edit, Settings, Green Frog you choose which fetched fields are shown, all of them by default, and then right-click a column header to tick the ones you want. Another setting in the same panel lets you choose which fields are fetched and which toolbox menu entries appear. This is a workable design, but it puts the burden of a clean Extra field on the user, and a library that already uses that field for other purposes will need a different storage strategy that the plugin does not offer.

An easyScholar account and secret key are required

The plugin is a client for a remote service, so it cannot work anonymously. The installation instructions have two steps. The first is to download the .xpi file from the releases page and install it in Zotero through Tools, Plugins, Install Plugin From File. The README also notes that Firefox users have to right-click the .xpi and choose Save As. The second step is the credential: register an account at easyScholar, log in, click the registered user name, open the user information page, open the interface access section and copy the secret key. That key is pasted into the Green Frog secret key input box in Edit, Settings, Green Frog. If you want the plugin to use a custom easyScholar data set rather than the default one, you have to log in to the easyScholar website, add the data set, and select it in the easyScholar browser extension first. The key is a credential for your easyScholar account stored inside your Zotero preferences, so the plugin inherits that service's terms and the availability of that service, and the plugin itself provides no offline mode.

Zotero 6, 7 and 8 users need different builds

The version matrix is the most easily missed detail. The README states that the latest version only supports Zotero 8.0 and later, that Zotero 6.0 users should download release 0.13.0, and that Zotero 7.0 users should download release v0.22.0. The badge at the top of the README reflects the same range, naming Zotero 8, 9 and 10. If you are on Zotero 7 and install the newest xpi because the releases page sorts by date, you get a plugin that does not match your client. The plugin's own configuration in package.json names the addon Green Frog with the addon id [email protected] and a preferences prefix of extensions.zotero.greenfrog, so the preference namespace is stable across versions, but the feature set is not. The release list shows a fairly quick cadence, v0.21.0 in April 2026, v0.22.0 in August 2026 and v0.22.2 a few days after that, and the default branch of the repository is bootstrap rather than main, which is worth knowing before you file an issue.

A toolbox that goes well beyond impact factors

Alongside the journal update, the plugin ships a set of editing utilities under Tools, Toolbox. The list covers bolding, starring, removing bold and removing the asterisk from author names, changing an author name to title case, and swapping the first and last name of an author, which is the fix for the common problem of a name imported with the family name in the given-name field. It also changes an item title to sentence case, does find and replace across item titles, changes the publication title to title case, and changes the publication name outright. The toolbox can show the Zotero profile directory and the Zotero data directory, which is genuinely useful when you need to know where a library lives on disk. Separately, the plugin can update a journal abbreviation with or without a dot, and it can be set to fall back to the full name when the abbreviation is not found. The abbreviation database holds only about five thousand entries according to the README, so the fallback is not an edge case for a large library.

Building the plugin from source

The project is TypeScript and uses the Zotero Plugin Template by windingwind, along with the Zotero Plugin Toolkit as its only runtime dependency, which is why the package is small. The scripts in package.json show the whole workflow:

"start": "zotero-plugin serve",
"build": "tsc --noEmit && zotero-plugin build",
"lint": "prettier --write . && eslint . --fix",
"release": "zotero-plugin release",

The start script runs a development server that launches a Zotero instance with the plugin loaded, and the build script type-checks before packaging. There is no test suite: the test script is a placeholder that echoes an error and exits with status one, so the plugin has no automated tests of its own, which is worth knowing if you are considering a fork. For local development the repository expects a .env file copied from .env.example, holding the path to the Zotero binary, the path to the development profile and optionally the data directory:

ZOTERO_PLUGIN_ZOTERO_BIN_PATH = /path/to/zotero.exe
ZOTERO_PLUGIN_PROFILE_PATH = /path/to/profile
ZOTERO_PLUGIN_DATA_DIR =

The example file also mentions a GitHub token for the scaffold to create a release and upload assets when publishing locally instead of through CI, and notes that platform-specific kill commands are already built into zotero-plugin. The tree itself carries the usual plugin layout, with src, addon, typings, a zotero-plugin.config.ts and an update.json that points clients at new releases.

Editorial conclusion

Green Frog fits a researcher or librarian who tracks journal quality metrics across a large library and already uses easyScholar, and who wants the numbers attached to the item rather than looked up by hand. It does not fit an offline workflow, since every update requires the easyScholar service and a valid secret key, and it does not fit someone on Zotero 6 who expects the current feature set, because the latest release only supports Zotero 8.0 and later. Verify first which Zotero version you run and download the matching build, then confirm that the Extra field is empty on the items you are about to update, since the README asks you to clear it manually when the display looks wrong. The licence field on the repository says AGPL-3.0, and the last push was on 2026-08-20 with release v0.22.2 on the same day.

Frequently asked questions

Official sources

1. Issues
2. License: AGPL-3.0
3. README
4. redleafnew/zotero-updateifsE on GitHub
5. Releases